arm64: dts: mediatek: mt8188: Add Global Command Engine mailboxes

In preparation for adding multimedia nodes and power domains, add
support for the two Global Command Engine (GCE) mailboxes found in
this SoC.

Link: https://lore.kernel.org/r/20240527093908.97574-3-angelogioacchino.delregno@collabora.comSigned-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

arch/arm64/boot/dts/mediatek/mt8188.dtsi

@@ -8,6 +8,7 @@
 #include <dt-bindings/clock/mediatek,mt8188-clk.h>
 #include <dt-bindings/interrupt-controller/arm-gic.h>
 #include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/mailbox/mediatek,mt8188-gce.h>
 #include <dt-bindings/phy/phy.h>
 #include <dt-bindings/pinctrl/mediatek,mt8188-pinfunc.h>
 #include <dt-bindings/power/mediatek,mt8188-power.h>
@@ -413,6 +414,22 @@ pwrap: pwrap@10024000 {
 			clock-names = "spi", "wrap";
 		};
 
+		gce0: mailbox@10320000 {
+			compatible = "mediatek,mt8188-gce";
+			reg = <0 0x10320000 0 0x4000>;
+			interrupts = <GIC_SPI 226 IRQ_TYPE_LEVEL_HIGH 0>;
+			#mbox-cells = <2>;
+			clocks = <&infracfg_ao CLK_INFRA_AO_GCE>;
+		};
+
+		gce1: mailbox@10330000 {
+			compatible = "mediatek,mt8188-gce";
+			reg = <0 0x10330000 0 0x4000>;
+			interrupts = <GIC_SPI 228 IRQ_TYPE_LEVEL_HIGH 0>;
+			#mbox-cells = <2>;
+			clocks = <&infracfg_ao CLK_INFRA_AO_GCE2>;
+		};
+
 		scp: scp@10500000 {
 			compatible = "mediatek,mt8188-scp";
 			reg = <0 0x10500000 0 0x100000>,